Plant cells have what is perhaps the most complex outer coverings. Plant cell walls are made largely of cellulose which forms strong, highly rigid, almost indigestible coverings that protect the cell and gives it shape.
<h2><u>Answer:</u></h2>
The 4 principle requirements for microorganisms survival are:
1) Food
2) Moisture
3) Warmth
4) Time
There are microscopic organisms that can develop in cold temperatures and some that blossom with warm temperatures.
A few bacteria go after the other microscopic organisms for survival. Different microscopic organisms get by getting supplements from dead items. Some microorganisms use photosynthesis to make their nourishment.
Answer:
The best answer to the question: If every gene has a tissue-specific and signal-dependent transcription pattern, how can such a small number of transcriptional regulatory proteins generate a much larger set of transcriptional patterns? Would be:
Because transcriptional regulators, which are the ones responsible for initiating, and stopping, transcription of RNA into protein, often work in pairs, one goes with the other, and thus increase the regulatory capabilities over gene expression so that the genes translated into RNA and then transcribed into aminoacids in protein chains, actually code for the correct protein types.
These regulators will both stand, as appropriate, on a specific gene to promote its transcription, or prevent it, depending on the different signaling mechanisms received.